Refrigerating apparatus



March 13, 1934- ALEXANDER 1,951,230

REFRIGERATING APPARATUS Original Filed Sept. 30, 1951 INVENTOR v. viu I ATTORNEYS Patented Mar. 13, 1934 PATENT OFFICE 1,951,230 REFRIGERATING APPARATUS Donald F. Alexander, Dayton, Ohio, assignor to Frigidaire Corporation, Dayton, Ohio, a corporation of Delaware Application September 30, 1931, Serial No. 565,973 Renewed April 19, 1933 16 Claims.

This invention relates to refrigerating apparatus and more particularly to electrical systems for refrigerating apparatus.

The objects of my invention include the pro- I vision of an improved electrical system for refrigerating apparatus, the provision of an improved method of supplying electric current to the fan motor of refrigerating apparatus, the providing of a method for improving the starting of the fan motor, and the provision of an improved control system for the fan motor of refrigerating apparatus.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a preferred form of the present invention is clearly shown.

In the drawing:

Fig. 1 is an elevational view partly in section of an i refrigerating apparatus embodying my invenion;

Fig. 2 is a section along the line 2-2 of Fig. l,

and

Fig. 3 is a diagrammatic representation of the Q5 driving units of the apparatus, of the control apparatus, and of the circuits.

Referring to the drawing and more particularly to Fig. 1, there is shown, for the purpose of illustrating my invention, a refrigerator cabinet 20 containing a food storage compartment 21. On top of the cabinet 20 there is supported a sealed unit 22 containing a single phase induction motor, generally designated by the reference character 23, which is provided with a suitable stator 24 mounted within the casing of the sealed'unit 22 and a rotor 25, of the squirrel cage type, which is mounted upon a centrally located driving shaft 26. This driving shaft 26 is mounted in the bearings 2'7 and 28 which are located within the upper and lower portions of the sealed unit 22. A heavy web 29 divides the sealed unit 22 into a motor chamber 30 and a compressor chamber 31. The compressor 32 is mounted upon the lower side of the web 29 and is driven by the vertical shaft 26. The compressor 32 discharges compressed refrigerant into the compressor chamber 31, from which point the compressed refrigerant is conducted through the conduit 33 to an air cooled condenser 34 situated at the side of the sealed unit 22. A receiver 35 is located at the bottom of the condenser 34 and receives the condensed refrigerant which is then forwarded under a suitable control through the conduit 36 to an evaporator 37 which is located in the 5 food storage compartment 21 of the cabinet for cooling food which is stored within the food storage compartment. The refrigerant within the evaporator 3'7 is vaporized by the evaporation of heat from the food storage compartment 21 and this vaporized refrigerant is conducted to the compressor 32 through the conduit 38.

A fan 40 of a suitable type is provided for blowing air over the condenser 34 and is driven by an electric motor 41 which is mounted upon the bracket 42 which in turn is fastened to the top of the cabinet 20. The motor 23, which is enclosed within the sealed unit 22, is supplied with electrical energy in the form of single phase alternating current through the electric conduits or wires 45 and 46. As best shown in Fig. 3, the stator windings 24 of the electric motor 23 comprise a main or running winding 47 and a suitable form of phase or starting winding 48.

Electric energy is preferably conducted from the electric conduits 45 and 46 to the running and starting windings 4'7 and 48 through the lead-in bushings 49.

A suitable switch 50, such as a switch operated by a thermostatic bulb in the food storage compartment, is provided for controlling the operation of the motor 23 and a suitable switch 51 is preferably provided for controlling the supply of electric energy to the starting winding 48. The switch 50 by reason of its thermostatic bulb or other suitable device, controls the operation of the motor 23 in accordance with the temperature of the evaporator 37 and the air within the food storage compartment so as to maintain a proper temperature within the food storage compartment 21. The starting switch 51 is prefer- 90 ably operated in such a manner that it is closed during the initial starting period of the motor 23 and when the speed of the motor increases to a suitable speed, this switch opens and allows the motor 23 thenceforth to operate upon its run- 5 ning winding 4'7.

The fan motor 41 is preferably of some suitable single phase alternating type such as a shaded pole type of motor having a suitable type of rotor 43. In Fig. 2 there is shown a 4-pole o shaded pole type of motor having its main winding 44 divided into the windings 55, 56, 57 and 58 each wound about one of the poles. At one edge of each of the poles there is provided a shaded pole such as the shaded pole 59 which is separated from the remaining portion of the pole by a suitable slot 60. This pole has wound upon it a short circuited turn or bare copper strap 61 which embraces this shaded pole 59 in the side portion of the pole face. This short cirno winding,

cuited turn or bare copper strap acts as a short circuited secondary coil, commonly called a shading coil, to produce a split phase effect which makes it possible to develop starting torque.

The main winding 44 of the fan motor 41 is preferably shunted across the terminals 63 and 64 of the starting or phase winding 48. The electric conduits 65 and 66 connect the main windings of the fan motor 41 with the terminals 63 and 64 of the starting winding 48. By such a connection, when the switches 50 and 51 are closed to start the motor 23, the electric current is supplied at line voltage through the electric conduits 45 and 46 to both the main winding 47 and the starting winding 48 and also to the main windings of the fan motor 41. It will be seen by inspection of the wiring diagram of Fig. 3, that when both of the switches are closed, the electric current is supplied from the conduit 45 through the switches 50 and 51 and the conduit 66 to the windings of the motor 41 and then through the conduit back to the electric conduit 46. Thus, during this time the main winding of the fan motor 41 is connected directly across the power supply line or the source of electric energy and in this way receives full line voltage.

However, when the motor 25 reaches its tripping speed and the switch 51 is open, the main winding of the fan motor 41 is disconnected from the source of electric energy or power supply, but it will be noted that a circuit remains which includes the starting winding 48, the electric conduits 65 and 66 and the main winding of the fan motor 41. At this time an induced voltage is set up within the starting winding 48 and by reason of this an electric current is set up through this circuit and during the time the motor compressor unit 22 is in operation, and the switch 51 is open, electric energy is supplied to the main windings of the fan motor 41. The voltage generated in the starting winding 48 during this period may not be equal to the line voltage but is generally somewhat less than the line voltage. For example, in one type of motor, when the line voltage is 110 volts, the voltage generated within the starting winding 48 will be from 60 to volts. The fan motor 41 is designed to operate normally upon from 60 to 80 volts and thus during the starting period it receives an increased voltage, resulting in increased starting and accelerating torques which facilitate and cause more rapid starting of the fan motor. Inasmuch as the starting switch 51 is closed for only a short period of time during the acceleration of the compressor motor 23, the current at line voltage is passed through the main windings of the fan motor 41 only a short time which is sufiicient for starting purposes but not suificiently extended to cause any injury to the windings of the fan motor.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. Refrigerating apparatus including a sealed unit containing a compressor for compressing the refrigerant and a single phase induction motor for driving said compressor, a condensing means situated outside of said sealed unit for condensing the refrigerant compressed in said compressor, a fan for blowing air over said condensing means, a single phase fan motor having a mai n and means for supplying said main rear winding of said fan motor with electric energy induced in said single phase induction motor.

2. Refrigerating apparatus including a sealed unit containing a compressor for compressing the refrigerant and a single phase induction motor for driving said compressor, a condensing means situated outside of said sealed unit for condensing the refrigerant compressed in said compressor, a fan for blowing air over said condensing means, a single phase fan-motor having a main winding, and means for facilitating the starting of said fan motor including a winding in said induction compressor motor for supplying said main winding of said fan motor with electric energy of a higher voltage during the starting period.

3. Refrigerating apparatus including a sealed unit containing a compressor for compressing the refrigerant, and a single phase induction motor for driving said compressor, said motor having a winding therein, a condensing means situated outside of said sealed unit for condensing the refrigerant compressed in said compressor, a fan for blowing air over said condensing means, a single phase fan motor having a main winding, and means for conducting electric energy generated in said winding of said induction compressor motor to said main winding of said fan motor.

4. Refrigerating apparatus including a sealed unit containing a compressor for compressing the refrigerant, and a single phase induction motor for driving said compressor, said motor having a winding therein, a condensing means situated outside of said sealed unit for condensing the refrigerant compressed in said compressor, a fan for blowing air over said condensing means, a single phase fan.motor having a main winding, and means for facilitating the starting of said fan motor including means for conducting electric energy at line voltage to said main winding of said motor during the starting period and for conducting electric energy generated in said winding of said compressor motor to said main winding of said fan motor during the running period.

5. Refrigerating apparatus including a sealed 120 unit containing a split phase motor and a compressor driven by said motor, a condensing means and an evaporating means situated externally of said sealed unit and connected to said compressor to form a closed refrigerating circuit, a single phase fan motor and fan driven thereby for circulating air over said condensing means, said split phase motor having a running winding and a split phase starting winding, said single phase fan motor having its winding shunted across the starting winding of the split phase motor, whereby said fan motor receives an electric current of higher voltage during the starting period of the split phase motor.

6. Refrigerating apparatus including a sealed 335 unit containing a compressor and a split phase induction motor for driving said compressor, a condensing means situated outside of the compressor, a fan for blowing air over the condensing means, a single phase induction fan motor 1 for driving said fan, said fan motor having a, main winding, said split phase induction motor having a running winding and a starting winding, means for supplying electric energy at line voltageto said running and starting windings, 145 means for controlling the flow of electric energy to the starting windings, said fan motor having its main winding shunted across the starting winding of said split phase motor for supplying aid fan motor with electric energy at line voltu.

age during the time the starting winding is connected to the supply means and for supplying said fan motor with electric energy induced in the starting winding when the starting winding is disconnected from the supply means.

7. Refrigerating apparatus including a sealed unit containing a compressor and a split phase induction motor for driving said compressor, said split phase induction motor having a running winding and a starting winding, a condensing means situated outside of said sealed unit, a fan and a single phase induction fan motor of the shaded pole type having a main winding, and means for shunting said main winding of said fan motor across said starting winding of said split phase induction motor for supplying said fan motor with electric energy induced in said starting winding.

8. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat exchange relation with the closed circuit including a second electric motor having one main winding, and means for supplying the main winding of the second electric motor with electric energy induced in the first mentioned electric motor.

9. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat exchange relation with the closed circuit including a second electric motor having one main winding, and means for supplying the main winding of the second electric motor with electric energy at a higher voltage during the starting period and at a lower voltage during the normal running period from the first mentioned electric motor.

10. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat exchange relation with the closed circuit including a second electric motor having one main winding, and means for supplying the main winding of the second electric motor with electric energy from the first mentioned electric motor during the running period.

11. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat exchange relation with the closed circuit including a second electric motor having one main winding, and means for supplying one of the motors with electric energy induced from the other motor.

12. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat exchange relation with the closed circuit including a second electric motor having one main winding, and means for supplying one of the motors with electric energy at a higher voltage during the starting period and at a lower voltage during the normal running period from the other motor.

13. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat'exchange relation with the closed circuit including a shaded pole type of electric motor, and means for supplying electrical energy to the shaded pole type of electric motor from the first mentioned electric motor.

14. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat exchange relation with the closed circuit including a shaded pole type of electric motor, and a single switch means for controlling the voltage applied to the shaded pole type of electric motor and a portion of the first mentioned electric motor while leaving unchanged the voltage applied to another portion of the first mentioned electric motor.

15. Refrigerating apparatus including a closed circuit having a pump for circulating the refrigerant through the closed circuit, an electric motor for driving the pump, means for circulating a fluid in heat exchange relation with the closed circuit including a shaded pole type of electric motor, and means for supplying electrical energy at a higher voltage to the shaded pole type of electric motor during the starting period.

16. Refrigerating apparatus including a compressor for compressing the refrigerant and a single phase induction motor for driving said compressor, and condensing means connected with the compressor for condensing the refrig- 

